[The specificity of antibodies reacting with Salmonella antigens in ELISA]

Among cattle sera from herds without a history of salmonellosis and without vaccination against salmonellas, we sometimes found samples which reacted positively in the ELISA with salmonella antigen. Contrary to antibodies caused by a proved salmonella infection, these antibodies could be eliminated by a whole-cell lysate of E. coli. In the colostra of cows which had received a salmonella live vaccine orally in the first days of life but were raised and kept without known exposition to salmonellas, we also found antibodies which reacted in the salmonella ELISA. They could not be eliminated by E. coli lysate.